Uncapped resit due to unclear Assessment Brief

Hi,
I had a programming course assignment that did have a very vague brief. The marking table never mentioned the provided professor code so I developed from scratch. In the assignment body there are words like: 'This is an individual assignment where you are expected to extend and implement the provided initial Java program source code based on the game', however it goes against the Learning Outcome section: 'LEARNING OUTCOMES
The learning outcomes (LOs) for this module are:
Knowledge & Understanding
LO1 Demonstrate a systematic understanding of the principles, knowledge and skills required to
design, implement, test and document programs written in an object oriented language.
LO2 Demonstrate a critical understanding of the essential principles and practices relating to
object-oriented programming, including the need for standards, principles of quality, and
appropriate software support.
Intellectual / Professional skills & abilities
LO3 Critically evaluate the methods and conceptual tools used in developing solutions to
programming problems.
LO4 Analyse, specify, design, implement and test a high-level solution to a programming
problem using object oriented and general imperative programming language constructs, using
appropriate documentation standards and software tools.
Personal Values Attributes (Global / Cultural awareness, Ethics, Curiosity) (PVA)
LO5 Effectively communicate development of a solution to a programming problem, including
critical evaluation.' and also it goes against anything on the marking rubric. The brief also never states that not using the provided code will have any penalty. I discussed with the professor and the program leader(and also with student success team) and they are totally against reaching any compromise, and totally discouraging me saying the only way is an Appeal but saying it is unlikely to win that. The code quality and the assignment requirements are more than met(I have around 7 year of industry experience so this level of coding is a piece of cake), however the grade was 43% due to this unclear requirement. I am planning to do an appeal, and even completely move universities if that is the case, but wanted to ask for some opinion if there is any way to solve this situation(what about contacting the head of the department foe example?)

Any opinion would be appreciated, especially if someone had similar experiences.

If the requirement said you "are expected to extend and implement the provided initial Java program" and you didn't use the provided code, and didn't extend it, then you haven't met the requirement of the assignment.
Even though the brief "never states that not using the provided code will have any penalty", it doesn't need to. You were asked to do X. You did Y. Hence why you lost marks.
During your "around 7 year of industry experience" did you make a habit of ignoring the stated requirement and just implementing what you thought was probably required?

If they are around, @gjd800 might have some thoughts.

They don't need to explicitly state that not using the provided code will incur a penalty.
The assessment requirement is precisely as DV has stated. You have not met that requirement, and it is very much an open-shut case. They don't need to look at anything other than that basic, irrefutable fact.
The assessment brief is not ambiguous by any reasonable measure; it explicitly tells you what to do, and you have simply chosen not to do it.
Any appeal wouldn't even get past the first administrator at my institution, and, not to be rude, I encourage you to take some ownership of this error of judgement. It is nobody else's fault.

And what would be the way to get an uncapped resit at your place, as for me personally getting this sort of service is a deal breaker and I am even having second though at continuing my studies at this institution.
If this is the standard for the UK institutions, then it is clear that the quality is not on par to what was promised in the beginning.